Evaluation of Udder traits in West African Dwarf Goats

Abstract

Udder traits of West African Dwarf (WAD) goats and factors influencing them were studied using 185 does located in South Western Nigeria. Traits evaluated were udder length (UL), udder width (UW), udder circumference (UC) and udder volume (UV). Others were teat length (TL), teat width (TW), teat circumference (TC), distance between teats(DT) and height of teat from the ground (HTG). Udder length was significantly (P<0.001) influenced by age, lactation status and liveweight. The increase in UL with age was quadratic. Lactating does had longer udders than non-lactating does by 1.93cm. Effects of lactation status and liveweight on UW were highly significant (P<0.001). Lactating does had wider udders (10.46­+ 0.30 cm) than non-lactating does (8.66 + 0.27 cm). Udder circumference was significantly (P<0.001) influenced by lactation status and liveweight. Lactating does had UC of 27.69 + 0.51 cm compared to 23.79 + 0.40 cm in non-lactating does. Age, lactation status and liveweight had significant (P<0.05) effects on UV. The increase in UV with age was significant, rising from 637.98 + 49.69 cm3 at 1-2 years to 934.51 + 75.90 cm3 at above 4 years. Lactating does had larger UV (923.43 + 39.97 cm3) (P<0.001) than non-lactating does (617.61 + 33.00 cm3). The mean values (+ s.e.m) for the udder traits adjusted to that of 3 – 4 years old lactating doe, were for UL, 11.6 + 0.17 cm; UW, 9.42 + 0.13 cm; UC, 25.69 + 0.44cm and UV, 817.93 + 25.92 cm3. Others were 2.19 + 0.03, 1.09 + 0.02, 3.40 + 0.05, 8.87 + 0.12 and 16.14 + 0.23 cm for TL,TW,TC,DT, and HTG respectively. This study showed that age, lactation status and liveweight are major factors influencing udder traits in West African Dwarf goats. A major advantage of this study is the provision of some basic information on udder traits of West African Dwarf goats.
Keywords: Udder traits, West African Dwarf goats